January Jones Shares Rare Photo of Son Xander to Celebrate His 13th Birthday: 'Bday Boy Is a Teen'

The 'Mad Men' star welcomed Xander in 2011, and has never publicly shared the identity of his father

January Jones is giving a rare glimpse at her son, Xander Dane.

On Friday, Sept. 13, Xander, the actress’ first and only child, turned 13, and she marked the milestone with a rare post about him on social media.

Jones, 46, shared a snap of her son posing in front of a sunset — and rocking head-to-toe sweats — on her Instagram Stories and wrote, “Bday boy is a teen ??.”

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The Mad Men alum takes her son’s privacy seriously, never posting his face and rarely posting him altogether — save for his birthdays.

She has never disclosed the identity of Xander’s father, previously telling The New York Times, "That's my son's business. It's not the public's business."

Last year, on Xander’s 12th birthday, Jones revealed a bit of his silly side, sharing an Instagram post of him dancing outside of Nobu Malibu. “Happy Birthday to my child. So proud to be yours,” she wrote in the caption, adding, “Couldn’t love you more.”

For his 11th birthday, Jones shared just a simple selfie — sans her son — in which she wore a tie-dye sweatshirt and large, orange sunglasses. "My son is 11yrs old today! I’m coping just fine (obviously), with grace and reflection,” she jokingly captioned the snap.

Related: January Jones Jokes That Her ‘Midlife Crisis’ Is All About Taking ‘Fashion Cues from Teenage Boys'

Since welcoming Xander in 2011, Jones has also been quite private about motherhood, sharing only snippets about her experience as a mom in interviews and during public appearances.

When Xander was just 4 months old, the actress said she was having a “blast” with the little one. “He’s wonderful,” she told PEOPLE at the time. “Every day he changes drastically — he’s getting really fun and giggly now, and I can play with him.”

"He’s not just a little bundle,” Jones added. “He’s taking shape, which is really amazing to watch.”

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Five years later, Jones opened up to Red magazine about being a single parent.

“Xander has a lot of bro time with the neighbor dads and my dad, who is super young,” she told the magazine at the time, noting, “It’s good to have strong women around a man to teach him to respect women.”

Plus, Jones explained, “He doesn’t have a male person saying, ‘Don’t cry,’ or ‘You throw like a girl.’ All those s----y things that dads accidentally do.”

“I just don’t feel I need a partner,” she added.

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Read the original article on People.